Regenerative gas-fired open-hearth furnace



July 28, 1931. w. scnucmqv 1,816,497

REGENERATIVE GAS FIRED OPEN HEARTH FURNACE U 7 Filed Aug. 24, 1926 6Sheets-Sheet 1' y 28, 19-31 w. SICHUCVANY 1,816,497 7 REGENERATIVE GASFIRED OPEN HEARTH FURNACE Filed Aug. 24, 1926' e Sheets-Sheet 2 y28,1931 J. W..SCHUCANY 1,816,491

REGEN'ERATIVE GAS FIRED OPEN amimi FURNACE I 7 Fi ed Aug. 24, 1926 G Sheets-Sheet 4s i l E 94 M '84 I y 1931 w. SCHUCANY 1,816,497

REGENERATIVE GAS FIRED OPEN HEARTH FURNACE Filed Aug. 24, 1926 6Sheets-Sheet 5 Has July 28, 1931. W.,SCHUCANY' 1 I 1,816,497

adnnnwxva GAS vmm ornn nmn'm mama fo -in s 24, 1926 s Sheets-Sheet smama 8 r I for:

Patented July 28, 1931 V venetian scene-any, or nonaluuun, GERMANYBEGElNL RiETIVE GASEIEEB CPEhF-HEAFEH FURNACE Application filed August24, 1826, SeriaLNo.

This invention relates to improvements in the working of regenerativegas-fired furnaces, more particularly of the open-hearth type, and itsobject is create for the furnace a perfectly positive or compulsoryconibustion process.

With this ob'ect in View accordin" to the present invention,

(l) the gas and combustion alr streams 19: issuing from the burnersreceive an equal,

or av predete mined different, heating dependent upon any existingcalorific value of the Working gas, by an adgustment of the h burneroutlet flue cross-sections'and a con, sequent distribution of theWaste-gas quantities over the re enerative heatin chambers, a l x (2)'1nconnectionlwlth the pos tive supply of the gas and air'quantitiesrequired 29 for a normal Working of the furnace, the

ratio of the burner outlet flue cross sections on the fresh gas side endis automatically adgusted corresponding to the existing calorific Valueof the gas. This adjustment done in such a Way that to the gas and airstreams similar energies of movement are imparted whereby with asimultaneouscorrespondin adjustment of the burner outlet flue axes anintersection of the gas andeir treains and thus the Whole combustionproc ess takes place on the bath surface only,

(3) the direction or inclination. of the burner outlet flue axes is'sochanged in a continuous alternation that a 'to-and-fro produced by theintersecting gas and air streams over the Whole bath surface isobtained,

(4:) said change of the directionor inchnation of the burner outletfiueaxes can be limitedto a certain area or pointof the bath surface,

(5) during the toand-fro travelqof the poin't of impact of the flame onthe bath surface, the velocity and direction of the air and gas streamsis controlled by varying the cross sections of the air and gas outletdepen. on. the distance from the-outlet as 'm the p of impact whilemaintaining revel of the point of impact of thefiamefi the amount ofpreheating required for the 131,246, and. in Germany September 1,1525.

lets constant,

theratio of the respective gas and air out- (6) the reversal of theburners from fresh-gas to waste-gas position, and vice versa, takesplacein relative dependence upon one anoth in such a Way that when reversingfrom fresh-gas to'wastegasposi I tion the burner then assuming Waste-gasp0 sition is at once again prepared for the reversal;

I Aecordingto the invention, furthermore, an improved arrangement forexecuting the; improvedcombustion process is provided, by which thefollowing advantages are ata F j fi Automatic adjustment'of theburnerstained to waste-gas and fresh-gas positiomtoyary the quantities .of'gasand air flowing [there-- through, Without the insertion of separatenozzles, in such a Way-that, on the one hand,

on the fresh-gasside the ratio of cross-sections of the burner outletopenings is, ac-

cording to the calorific value J(hereinafter' briefly called; value) ofthe working gas,

such that to the gas and air streams,lwith' any value of the gas,energies of movement are imparted which are 'approximately similar, sothat both currents intersect one 1 another on the bath surface and thusthe combustion process actriallytakes place on the bath surface only,While, on the Wastegas side the ratio ofcro'ss-sections ofthe" burneropenings is regulated depending upon the calorific value of the fuelfgase. g. when gases rich in fuel const tuents aroused small in comparisonto the air outlet, Wherey as when poor fuel gas is used thecrosssectional area of the gas outlet is proportionally a,

larger and approaches or may even attain,

the cross sectionalare'a of the air outlet The sum' of. thecross-sections of the .gas a to the largerguantitiee' etwastmgas low apassage resistance as possible, is larger than on the fresh-gas side.

(B) vSweeping, in a continuous succession, of each point of the bathsurface by the flame produced by the intersecting streams streamsissuing from the burners met on an extension of the axes of the twoflues on the bath surface. This could however not be attained with fixedoutlet flue crosssections. With regard to fresh-gas conditions, the out-9, let' c'ross-section of the flue hashitherto been kept small in orderto project the gas stream at high speed onto the bath surface,

but since on the other hand with regard to the considerably largerwaste-gas volume V ithe total cross-section of the gas and air fiuesofthe, waste-gas burner must not he reducedbeyond a certain minimum, theair flue opening relatively 'to' that 'of the gas flue must be, chosenso large that the burner, 9,, for supplying as uniform quantities aspossible through both, fiues per unit of crosssection, thatis, persquare metre, does not even suffice for working with gas of highestvalue, for which theair quantity amountsto a multiple of the gasquantity. The air quantity .due to. its low energy of movement,resulting from. the too large outlet flue cross-section, does not reachthe bath surfaceatallbut itis upwardly deflectedby q its buoyancyimmediately after its escape 7 fromthe burner, While the currentof hgher energy of movement does reach the bath surface but 1s then alsoupwardly de-' fie cted. 'Gas and airparticles come thus in 5, contactwith one another and are not ignited on the bath surface, but fartherupwards directly beneath the top wall-of the furnace. The priorcombustion process is thus not at of the flameby the separately arrivinggas stream, andfurthermore the whole combus-' fixed outlet fluecross-sections, did-not even suit the simplest requirements fo'rthe furnace working with a gas of -approximatel constant value. Saidrequirements-can after 7 all be compliedwith only by the provision ofmeansfor perfectly adapting the energies of movementof the-gas and aircurrents to 1 one an other, and -inlaccorjdance with changes Perfectlyautomatic working of the all ideal, because the top wallof the furnace Vnighly'strained by heat Whereas the bath i itself'is'rather cooled atthe point of impact,

in the value of the gas necessary Cluringthe working of the furnace andrequiring a variation in the ratio of quantities of gas and air, andthus of the speeds- Furtherr more, with increasing value of the gas alsoits specific weight isdecreased whereby the outlet flues, must befurther increased for attaining an intersection of the two streams onthe bath surface. For attaining said absolutelynecessary control of theenergies of movement of the gas and air streams, the followingcgnditions must be accomplished:

(1) a positive supply of the gas quantity required for a normal workingof the furnace according to the gas value, and of the air quantityrequired therefor,

(2) a control of the ratio of outlet cross- I sections of gas and airfiues corresponding to the actual quantities supplied and to thespecific weight of the gas.

An equal, or a pred termine'd difference as the case may be, heatingofgas andair, and furthermore the adaptation ofthe energies of movement onthe fresh-gas side, for at-' taining an intersection of the gas and aircurrents on the bath surface, can be attained preferred arrangement forexecuting the improved process of heating open-hearth furnacesz 1 7 Fig.1 shows that part of the main conupon the flap positions; v

Fig, 2 shows the mechanism for adjusting the flaps corresponding to thevalue of the heating gas;

Fig. 3 shows thesuspension of the main 7 control spindle and thedrivinggear for the latter and the, auxiliary, control spindle,

application of the invention to a furnace, the line A-A indicating theaxis'of symmetry of the improved arrangement;

Fig. 5 shows a general diagram contai n the parts shown in Figs. 1,2 and8;

Fig. 6 shows a diagram of the burner flaw positions for the gas and airflues indicat their adjustments in accordance with the value I Fig. 7 isa section on vthe line 7? of Fig. 3; Y I

ratio of cross-sections, of gas to airv channel trol spindle whichserves for directly acting ioo Fig. 4 is a sectional diagram showing the1 r I v r 8 1S a section on the line 8-8' of- Fig. Fig. 3; I Fig. 91's alongitudinal secticnfhrougha flap showingthe cooling'thereof;

10 isa side view of the correction mechanism in the fresh-gas and wastegas position as well as of the device for reversing from fresh-gas towaste-gas position;

Fig. llis a section'ton the line .1111 of Fig. 2; V

Fig. 12 is a section on the line 12 12 of Fig. 9.

For the purpose of providing-the ends of the gas and air .flues oftheburner heals respectively with ad ustable outlets (for the fresh-gassupply), and adjustable inlets (for the Waste-gas withdrawal) top andbottom" surfaces of the two flues in front of the gas between the burnerhead and furnace interior are formed as water-cooled (indicated at 11,Fig. 9) turning-flaps 1, 2, 8, 4- (Figs. 1 and 5), the flaps 1 and 2belonging to the air flue and the flaps 3 and l to the gas flue.

In order to make a prior'combustion by a premature contact between gasand air impossible, between the two middle flaps 2 and 3 a likewisecooled partition-wall 5 (Fig. 5) is provided and firmly connected withthe outer casing of the two fiues, said wall extending directly to thegap between burner head and furnace interior. The turning of the flapsis effected about hollow. shafts 6, through which water is passed andwhich are rigidly mounted in the outerfcasine; of

the furnace, the several operating-rods 7,;8,

9, 10 for the flaps being arranged on the outer ends of said shafts.

The arrangement of the mechanism for V actuating the burner flaps asshown in Fig.

i is for sake of clearnessonly, the control spindles 14 and 18(hereinafter explained) being arranged in practice external to-the letcross-sections of the gas and air flues. corresponding to thequantitiesof gas and air flowing therethrough corresponds to a -fixedralue of the gas, or to the specific ht of the gas, in such a waythatwith v supply of the quantities of gas and an q'uired for said valuethe energies of movement of suit one another that an intersection ofboth said streams'xtake's place on the bath surface only. Furthermore,for attaining a travel of the point of impact of the flame over the bathsurface, on the onehand, the direction ofthe burner outlet flue axes 1-spondingly displaced and, the er hand, the outlet openings of g andburners must he or widened corrc respective positions t is gas and airstreams so! as corn 1 sponding tothe removal or to the approachment ofsaid point of impact from or to the placeiof issue of the supply, thatis, the supplying burners, for adapting the energies of movement of gasand air to the different lengths of (the paths taken by the gas and airstreams; in which connection, it must be noted, however, that the ratioof outlet crosssections of the gas andairflues per se, suit ing theactual gas value, must always be kept constant..For a displacement ofthe burner axes during the travel of the point of impact of the flame onthe bath surface, the

main control spindle 14, to which the operating-rods 7, 8, 9, 10 arelinkechis moved up and down in a continuous alteration by turin'g to theright or to the left, for which purpose it is mounted with its upperscrewthreaded cnd in asliding nut 29. The latter is, in cross-head likefashion, clamped in a fixed race, member 30, so that it cannot execu eany movement during thisperiod- The adjuscment of the actually requiredflue cross-sections: takes place as follows: The free ends of theoperating-rods. are not dircctly connected with the main control spindle14 but located in'adjusting nuts27, 28 by a slot-and-pin connection tosuit the changes of length of the rods when turning. Said nuts 27, 28are screwed upon externally screw-threadedsleeves.15,15 and v16, 16.

Said sleeves are placed over the main control spindle 1 1 and providedwith an inner guiding groove which is in engagement with a key 124 onthe main control spindle 14-, whereby the sleeves can beverticall'yshifted on the main control spindle but are compolled} to participateinthe'rotations of the latter. As hereinafter explained, {said sleevesare locked in positionon the main control spindle relatively to oneanother by means o-f-regulating bushes 17, 17 serving YThe directions ofthe screw-threads ofthe sliding nut 29 and of the two sleeves 15,15 (forthe air flue) and 16,16 (for the gasflue) are such that the adjustingnuts 27 (for the air flue) and 28' (for the gas flue) are. during onerotary. direction of the main control spindle 14 a preached to, andduring the other removed for the control in accordance with the actualvalue of the gas.

from, one another, said removal takingplace during the downward movementof said. approachment during the upward movement of the main controlspindle.

Adaptation of the burner outlet openings to the qua'ntities of gas andair flowing therethrough and changing with the gas value V I i By theabove-describedarrangement, the

displacement of the point of impact of the flame-and the adaptationcfthe burner out- I,

let oncnins's thereto recited. Si cedurthe travel of the -ooint ofimpact of fianieon the bath surface the ratio of outlet cross-sectionsof the gas and air fines for the actual gas value'must be independent ofchange of the outlet openings and thus the act upon the operating-rodsfor an tment of the burnerflaps: to a fixed value. ushes 17 (air flue)"and 17" (gas flue) are provided, of which each engages by screw 1threads over each pair of sleeves 15, and

f'tion with reference to the main control 1G, 16. Said regulating bushesare rotatably mounted upon an integral guiding col- 28of the maincontrolspindle 1 1-, where byalso the sleeves receive their fixedposispindle 14:. Obviously, each pair of sleeves are moved toward oraway from one another by correspondingly turning the regulating'bushesl't', 17, whereby the flaps of the gas and airlines vary thecross-sections thereoi independently from the other action of the.

maincontrol spindle 14 upon the same. The regulating bushes are driveneach by a toothed gearing 57, 107. and 57, 108 respec- "tively fromv theauxiliary control spindle 18 for theadjustment of the gas value, whichspindle: is mounted" in brackets 24:, 25 (Fig. 2).

lV'ithreference to the control of the ralue' the followinglinust benoted; generally For controlling the whole range from 1100 calories percubic nietreh (pure blast-furnace gas) to-lOOO'calories per cubic metre(coke gas), the ratio of the burner outlet cross- 35isections of the gasand air fiues must be variable from 1: 1.1 (pure blast-furnace to 11 1.0(coke gas)l- The action upon the flap positions for changing the ratioof cross-sections ofthe air andgasfines is with the improved arrangementsuch that .al-'

crosssection remainsconstant (flap posi{ "tion F), Fig. 6) while thegas-flue cross-section is gradually narrowed from the position 0 tothe'position (Z, Fig. 6. In'order to permit the regulation bushes forthe gas and all fines being driven separately, the two driving toothedwheels 107for 17.) and108 (for 17) are loosely mounted on the auxiliarycontrol'spindle 18 and can be coupled therewith by means of the twoclutches 19 (for 107) and 20 (for 108) respectively,

which are positively connected a. double link 21, 21. in such a way thatclutch 19'is in eng ment when clutch 20 is disengaged, and we verse.Both clutches as as their links do not exert a pressure-=thereon,

a" n constant, it must be possible *to sepa Forthis purpose, theregulating always held positively in disengaged posh tion by springact1on.

The control during the adjustment ofa' ratio of cross-sections from 11.151t0' 1 1.0 is as follows: Driving of the auxiliary con.-

trol spindle 18 is effected from the shaft 3 1 V (Fig. 5) by thebevelgearing 38 (Figs-. 2 and 5). The clutch 19 is supposed tofbe stillinengagement from the preceding play. The screw-threads of theregulating bush 17 are so chosen with reference to the rotary directionof the driving shaft 34 that the two sleeves 1'5, 15 are approachedto-hone another whereby the outlet cross-sectionof the air flue 1Sgradually widened. The lower endof the'sleeve 15-- is fitted with anabut ment 56. As soon as the ratio of cross-secto air outlet) by thedisplacement of the two sleeves withreference to one another, the

abutment 56 strikes uoon the ear lever 22' fulcrumed at 72, wherebyclutch 20' is engaged and the sleeves 16, 16 are removed? from noanother by the regulating bush 1'! and conse 'uentl the as outletcrosstions has been changed to 1:1.5 (gas outlet section narrowed. (seediagram, Fig.

Immediately. after-the beginning of this" movement, the abutment" 56(Fig'.- 2) of the sleeve 16 frees the lever 28 fulcnumed at 7'3,.whereupon clutch 19 isautomatically' disengaged.

with the main control-spindle:

Coupling of the aux liary control spindl'e The driving of the shafts 33,which actupon the main control spindles by means of the bevel gearings35, and of the'shaft 8-1, which acts upon the auxiliary controlflspindle 18 by means of the beveligearing 38, is accomplished by'separatvand" inde- Theuncoupling of the motor 123 from pendent controlsystems operating through a common drivmg motor-129 (Figs.v '4- and theshaft 34 and-its coupling with the" shafts 33, or vice versa, takesplace by acorrespondlng displacement of a hollow" shaft 224 mounted 011'the extended motor shaft 223v and on one end; of which one of the twobevel wheels of a bevel gearing 225' for the driving 'shaft' i ltisarranged'whil'e on the otherend the clutch 226 for driving the toothedgearing 55' (hereinafter men- I tioned) is located. The reversal ofdirection of the motor 123 itself.

Theauxiliary control spindle 18 is coupled with the main controlspindleonly during the adjustment to another gas value, by the toothedgearing 57, 108 or'57,107 respectively, which coupling. takesplaee'automaticala ly in such a wayithat during. the drive of the shaft 34 theropes 66 are wound-up? on a pulley 68 mounted ona friction cone 69 keyedon the shaft'34e; whereby, with the;

aid of links 58 pivoted to pressure I l it'l (Fig. 2) the toothed wheels*57',

the shaft 34 can be effected by reversing the rotary] loosely mounted onthe bushes 17, 17, are pressed with their toothed faces 60 against alikewise toothed projection 61'of the regulating bushes 17, 17andthereby coupled with the latter. 'The friction between cone 69 andgearing pulley 68 can be regulated by a corresponding adjustment of thenuts 70 in such a way that, on the one hand, the

counter-pressure of thedisengaging spring 74 (F 1 and 5) is overcomeduring the rotation oi the driving shaft 34 by pulling the ropes 66 anda corresponding contact pressure between the toothed wheels 57 and thetoothed projections 61 of the regulating bushes is produced by the links58 while, on the other hand, the friction is not so strong that thereexists a danger of a breaking of the ropes 66 and of the links, so thatthe pulley 68 begins to slip on the friction cone 69 at a'certaintension of the rope. For indicating the adjusted ratio of the fluecross-sections corresponding to the actual gas value, a runner 71 isarranged on the drivingshaft 34 along a scale 71' (Figs. 3,

4 and 5) having charactersor numerals thereon indicating the value ofthe gas corresponding to said ratio.

Thus, as soon as a change in the value of V the heating gas takes place,the shaft 34 is put in gear by a displacement of the hollow shaft 224whereby the toothed gearing 55 is disengagedtherefrom. After indication:by the runner 71 on the scale 71 of the ratio of cross-sections of thegas and air flues then required, the hollow shaft 224 is again broughtinto its coupling position with the toothed gearing 5 5. V I

Reversal of the furnace working:

Hereinafter, the total working'jof the arrangement and particularly itsreversal to Waste-gas or fresh-gas position respectively, is to bedescribed (Figs. 3, 4 and 5). The motor 123 acts, unless with a changeof the gas value it is, as mentioned, connected with the common drivingshaft 34 of the two auxiliary control spindles 18 by the toothed gearing55 alternately upon each of' the two driving shafts. 33 of the maincontrol spindles 14, that is, that, controlling 'the fresh-gas side. In'orderto change the rotary direction of the main control spindle 14during the up and down movement of the same without requiring a changeof the rotary directionof the driving motor 123, on each driving shaft33 of the two main con trol spindles 14 apair of oppositely disposedbeveled gears is mounted, that consists of two loose wheels 84 on thedriving shaft 33, which can be coupled therewith by means of theclutches 40, 41 and which are both in gear with'the common driving wheel85 keyed on the intermediary shaft 49, and respectively, betweenmotor-driven toothed gearing and the double bevel-wheel pair. The,operation of the clutch actuating rod 43 is effected bya runner 48, or101 respectively, screwed on thecontrol threads '86 of the driving shaft33 and prevented from turning thereon, so thatit ismoved to and froaccording to the rotary direction of'the driving shaft.

- The control takes place as follOwst- It may be assumed that clutch 41is engaged and the runner 48is moving along the control threads 86 fromthe right to the left, which corresponds to the travel of.

the point of impact of the flame from the nearest to the farthest(distant) 'place of impact of the fuel and air on the bath, or Irespectively to the descent of the main con-' trol spindle 14. Aftercompletion of the rotations of the driving-shaft33 required for theextent of said control threads the runner 48 strikes against the fixedabutment 44 of the clutch actuating-rod 431 and re- .95 48 strikesagainst'the abutment 45, whereby. V i

again the reversal to the opposite rotary direction of the driving-shaft33 is effected.

This to-and-fro play is repeated until a reverse] of the burner towaste-gas is required.

Reversal to 'waste-gas:.F0r the adjust;

mentof the nozzle flaps 1, 2, 3 and 4 to waste-gas, the abutment 45. ismanually turned out of the path ofthe run'ner48, the different partsthen move as follows: Themain control spindle 14 ascends; The point ofimpact of the flame travels to thenearest place of impact to theburners, that is the outlet cross-sections, at the burner head arewidened, and the runner 48 moves along the control threads 86 from theleft to the right. The proceeding must then belikewisecom tinued, thatis, the runner 48 must further move along the controlthreads 86 to theright beyond the abutment 45 which for this purpose isturned aside (Fig.10), until'the opening of the nozzle flaps corresponds to the waste-gasposition. L Then, however, the l control spindle,14 screwing into thesliding-nut 29 would ascend far beyond the position corresponding to.the nearest' point of impact,-that,is the position of the "nozzle flaps1', 2, 3, 4 would have too steep a downward direction when the waste-gasopening is attained. To prevent this, means are provided forpermitting,"at the reversal to waste-gas and at acertain pointof'themovement, a further rotation of the main control spindle 14 butpreventinga further ascent of the same. For this-purpose, the

therace member 80. .(l 8) out be locked and unlocked there n.

v h sliding -29 .te msh s the 5 is? rsupiler iss" ear n t r t m co trolspindle 14:, its unlocking i 'ointhe fixed her-50 can takexpiacegonlyWith pro; n of another hearing for the I1 icon rol spindle. For thispurpose, below the screw-threads for the sliding-nut 29 otherscrew-threads are provided on the i pper end of the main control spindlefor .c" gagement with the thrust-hearing d sc 7 I8 8. Both said.screw-threads run in the ie direction, so that, when screwing-up Y Ithe n ain control spindle into the sliding-nut,

- the (thrust-bearing disc 88, which is prey ted frpni rotationbyclamping-members ual pitch of bothfsaid screw threads,

is erence'to the driving-boss 36, against the u per surface of which itto beer at the innient of the intended fix d position of height gt themain control spindle after the reversal ofthe burner to waste-gas orderto selile/thenas a {substitute -ior the supporting of the nain controlspindle, 'preyiously ter d b the sliding-nut 29,

thenunloclzed from the race menu'- her 305 .pitcli ofthe threads of the.thirnstebearing disc must be somewhat higher; As a reversing point towaste-gas position, theiplaceo t the nearest point of i, pactisfc hosen.Themain control spindle isth en infitshighest position, and the runnerd8 has arrived et the placeof the then disengagedabutment 45, so thatthe drivingfshatt BS' r presented in the same direcp Thethrnsti-bearing.disc88 hasbeen screwed tow rd and eta short.distange fron acorrespond projection of the drivingbossfifi'and itQhas becomedisengagethhy a pull on the rope 91 attached thereto the lfeftehandclampingcontrivance 92 of the .slidingrnntlQQQ The latter would then beiiurther clamped by the right-hand pcl ain ping-c ontrivance 93 only,which is howe ls'c disengaged by action of the runner 48ft ,nntlielev eriid to which the rope 95 is nttnche d. The two clainping contrivances.Ia're n oiu ted each on. caselilreprojection oi the race member 7') andtheir construction is .cleariy ,ob rious from land 7 'At the iinprnentwhen the thrustrhearing disc 88 bears gains he d ngss 36,

the clam ing lnernbers 89 must have freed L 0 7 theirotation of thedriving-boss 36 and thus ofthe main control spindle 14-. The ofthe-thrust-bearing disc 88 is etfected iii f h a .waylthat the clampingpr s d o en on n ther isscrewed down. With woiild no change .ettl1e.positi.on' height ofthe thrust-hear ng d1sc 88 with the disc, soYtliatthe same can participate by means-of blade springs -(F-ig.

The clamping members- 89 are located in a recess of the thrust-bear ng dsc 88. They must thus part clpate 1n the up and down movement .of thesanie, but are prevented froniturning; Said clamping members are openedfor free ng the disc 88 by rotation oithe cams 98 mounted on thedisengaging shafts .97. Said cams are provided with inner gu dinggrooves by whlch they can move up and down along guiding keys pro videdon the d1sengag1ng shafts 97 for the distance of the, path of thethrust-bearing disc. The operation of the disengaglng shafts is effectedby bevel-wheel pairs 99 (Fig 3) from levers 100 arranged in 1.351 6 .f on the upper surface of the driving boss 36. For this distance, thus,themain control spindle 14 drops whilethe jaws ofthe slid- 7 ing nut 29turn the levers 100 downwards,

whereby the cams 9,8 assume such a position" that the clamping membersfree the thrust-bearing discv 88.

boss 36. A further screwing of thesa ne on the main control spindle isnrevented .bv

l friction of the contact faces whlchis further the sliding nut 29 onthe spindle id, is Sa d levers 7 H p The latter bears thenagainst theprojection of the drivingincreased b 7 the preferable toothed wei 'ht ofthe nain control spindle then "from the thrust-bearing disc. The maincontrol spindle maintains thus its actual position of height, while withcontinued rotationin the same direction a further screwing-asunder ofthe nozzle tape 1, 2, 3, 4 takes place by'an approachnient of the nozzleadjusting nuts on the pertinent suspended sleeves 15, .15", 15, 16 untilthe" required 7 waste-gas opening'is attained. The sliding nut i 29 hasmeanwhile been screwed down for a corresponding distance on the inaincontrol spindle, while the runner 4L8 has further moved in the hithertodirection to the right on the control threads of the driving-shaft 33.Shortly before the attainment of its position on the co3'1trolthreads 86corresponding to-the waste gasposition of the nozzle flaps -1, 2, 3, itherunner 4L8 embraces with' its ,lower arm the doublearlned lever 53,the other arm otwhich acts upon the clutch. rod of .the mainnnotor i to;

'7 clutch-es sol "tch 51 in such way that e ii i b i 191' is put towork; In this nection, must be noted that the motor are by springpressure continuously held in disengaged position, unless they are acted'upon'by the lever 53 for clutch 51 and 53 for clutch s The two gearinglevers 58 are mounted on a common shaft 51 forming the fulcrum for thesame. Then for a shortmoment, 'themechanism for both furnace sides is atworlz, the runner 101 of the right-hand side inovi to the right andfreeing the lever 53, so that motor clutch is disengaged by its springpressure. The runner 48 is then in a position corresponoing to thewaste-gas opening, and it has struck in the meantime, intermediatetheputting-in gear of the motor .clntch' 51 and the puttingout-of-gearof the motor clutch 52, with its upper arm against the fixcd abutment109 and by therclutch actuating-rod l3 disengaged the clutch 40. andengaged the clutch 41, t us preparing the waste-gas side on the left ofthe furnace for the reversal (F gs. 8 and As shown in Fig 4c, the wholemechanism of both furnace sides is perfectly symmetrical (see axis ofsymmetry AA) and thus similarly operated oneach furnace sideincorresponding alteration, the proceeding in backward direction, e.waste-gasto fresh-gas position, on the hand side being now described: v

' On the right-hand side, the analogous proceeding has been COIDPlQtGCland the runner 101 has returned to its end position to the left for,-waste-gas position "of the right hand side, the motor clutch 52 beingagain eftengaged by lever 53. The runner eTS of the left-hand side isthus again on its travel to the left and has freed the lever 53, wherebythe motor clutch 51 is automatically disengaged. The main controlspindle14 main tains still its highest position, the outlet cross-section isgradually narrowed more and more by the then occurring removal of thenozzle adjusting nuts 27, 28 from one another, and the sliding-nut 29 is:being screwed upwards on the vertically fixed main control spindle 14.The left-hand clamping contrivance 921s heldiin its disengaged positionby the rope 91 attachedto the clamping members'89 until thethrustbearing disc 88 after engagement of the clamping members 89 hasagain been screwed up for a certain distance on the main con,- trolspindle 1 1 with the thenexisting rotary direction of the latter.AsJsoon as,.thus, the sliding-nut29 has attained its highest position,it is automatically locked by theLengagement of a suitable notch thereinwith the only loot-h of the right-hand clamping contrivance 93, which iscontinuously kept in working posit-ion; A Asthe clampingmems bers 86have lirmly engaged the thrust-bearin the dir/ tio ing disc 88 after thelevers 100 have been turned up, the tl'irust-bearing disc is screwed upwhereupon also the left-hand clamping 'cont'riva'nce comes to action. vThe main control spindle begins to screw downwithm. the guiding-nut 29from 1ts hithertorra1sed po-v exactness is'to be considered, Withinwhich the an'angement works during the whole ads justment to a fixedvalue: of the working gas and during the sweeping of the bath sur- P LJ. 1 J. race. It may be assumed that the COTIGCJ ratioof cross-sectionsBXlStSfOl a hxedvalue with a burner adjustment to the nearest.

point of impact of the v flame. With a changeof the burner flappositions for displacing further the point of impact, the

initially correct ratio of cross-section tests varieswithin certainlimits. theangles,

for which the flaps oscillate, must normally remain constant forallowing a sweeping; of the total bath surface in question at any gasvalue, said variation of the ratio of cross-sections istheflarger,the-smaller the outlet cross-section in: question at thenearest point ofim'pact, orithe higher is the value of the gas.Furtherregard must be paid to the diiference'in the specific weights ofgas and air increasingmore and more with increasing gas value.

Correction apparatus;

Said inexactnesses are dispensed with by the present invention in such aWay that on the fresh-gas side the diilerenceof the resulting energiesof movement of gas and air does not exceed 15%, while on the wasteofthe. heating temperatures of gas and-air of less; than, 10 0'only; Thisis attained by, a correction" apparatus (Figs. 1 and 11) effecting onthe fresh-gas side aswell as on i the waster-gas side a correspondinglimitation of thewidening ofthe outletcross-section ofthe gas fluedepending upon the gas value. V I

Hence it follows that acorrection apparatus must be used, auxiliarycontrol spindle 18, the driving of the sleeve 76; beingfleflected. bymeans of the toothed gearing 57 181'. of said-sleeve76 a boltf77, 78 isscrewed and fitted'each witha bounding arm'79 for the fresh-gas and, 180 for ,the waste-gas adjust v which is; operated by the In each endside the adjustment permits a difference r 5 ment. The direction of thethreads in the sleeve 7 or on the bolts 77, 78 is such that with theadjust; out for ahigher g=-s value the bolts are s ed out of the sleeve76 and adapted, b the bounding arms TS f-or 7 l Jtreshs supply and 80for waste-gas w thdrawal. LO hi i the widening of the flue .L' l 1 1 .1?outlet cross-sec ion by the yiel-aingly on the bat-l Furthermore, itmust be noted that by a cor arranged-eperating rods 9, 10 (Fig. 1)bearing upon the surfaces of the arms. As shown in Fig'll-for oneoperating rod 10, the operating rods 9, 10 are each two-parted, one par10 being arranged on the turning flap (4) and embracing theothcr part10' that is linked to the main control spindle 14-. A bolt 81 fixed onsaid latter part engages in borings of the other forked part 10 while aspring 82 encased at 81 allows a certain degree of movement between thetwo parts 10, 10. .The bounding arms 79 for freshgas supply and 80 forwaste-gas withdrawal are arranged at an angle of 90 to oneanother. Whenreversing from fresh-gas to waste-gas position, and vice versa, eachtime the respective arms are turned into working position and heldtherein until the next reversion takes place. Fig. 10 shows that saidreversal can be effected in a simple way, simultaneously withv themanual turningaside of the abutment 45, by means of the draw-bar 124:.To prevent collision between the operating rods 9, 10 and the boundingarms 79, the reversal .must take place when the runner 48 lies at theabutment 4% (farthest point of impact of the flame) The wholearrangement worzs thus perfectly automatic, and that for both mainoperations: for the adjustment to a fixed value of the working gas andfor the continuous sweeping of the whole bath surface, that is for apositive combustion directly surface. The control of the blowersfor gasand air, of which the capaci-, ties must be varied corresponding to the"quantity of gas and air to be supplied according to actual gas value,can be made dependentupon the runner 71 for indicating a certain gasvalue. The reversal of the arrangement at the change of'direction of thefurnace working takes place ina simple Way by manually putting the.abutment 4 5 into 1ts'd1sengaged or work ng positions.

ment of the main operating elements, of.

allows combinations which make the ap paratus more than hitherto adaptedfor the various requirements of the furnace Working. I

What I claim is:

1. The method of vv'orl ing furnaces having air and ga heating checkerchambers, a bath receiving iearth and burners at opposite ends of thehearth, said method comp-rising preheating the streams of andair forcombustion to equal r predetermined different temperature for eachthermal value of the said preheating being doneaccordin to the principlethat the greater the calor c value of the gas the smaller the amount ofwaste gas necessary for the preheating of the gas in relation to theamount of waste gas necessary for the preheating of air and vice versa,and adjusting the cross-section of the burner openings at the outlet endof the furnace so that the greater the calorific value of the gas thesmaller the proportion, according to which the waste gases aredistributed to the gas and air chambers.

2. The method of working industrial gas furnaces havingair and gasheating checker industrial gas chambers, bath receiving hearth andburners at opposite ends of the hearth, said method comprisingpreheating the streams of gas and air forv combustion to an equal. .orpredetermined dlfferent temperature for each thermal value of the gas byan adjust ment ofthe burner outlet fiue cross-sections on the Waste gasside and a consequent distribution of the waste gas quantities over theregenerative heating chambers, said preheating taking place according tothe principle'that the greater the calorific value of the gas andconsequently the ratio of'the amount of combustion air to the amount ofheating gas, the greater must be the ratio of opening on the waste gasside and vice versa, andautomaticallyad usting the 1'at1o of the burneroutlet cross-sections on the freshas of the two streams takes place'onthe bath surface, the burner outlet flue axes being simultaneously andcorrespondingly adjusted and the Whole combustion process taking placeon the bath surface only.

.3. The method of working industrial gas furnaces having air and gasheating checker the air" burner opening to the gas burner chambers, abath receiving hearth and bum ers at opposite ends of the hearth, saidmethod comprising preheating the streams of gas and air for combustionto an equal or predetermined different temperature for each thermalvalue of the gas by an adjustment of the burner outlet fluecross-sections on the waste gas side and a consequent distribution ofthe Waste gas quantities over the regenerative heating chambers, theratio of the burner outlet cross-sections on the fresh gas side beingadjusted automatically in such a Way that in connection with thepositive supply of the gas and air quantities the energies of movementof gas and air streams for each thermic Value of the gas have such avalue that the intersection of the two streams takes place on the bathsurface, the burner outlet flue axes being simultaneously andcorrespondingly adjusted, the whole combustion process thus taking placeon the bath surface only and the inclination or direction of the burneroutlet flue axes being changed in a continuous alteration, so that a toand fro travel of the point of the impact of the flame produced by thein tersecting gas and air streams over the whole bath surface isobtained.

4. The method of Working industrial gas furnaces having air and gasheating checker chambers, a bath receiving hearth and burners atopposite ends of the hearth, said method comprising preheating thestreams of gas and air for combustion to an equal or predetermineddifferent temperature for each thermal value of the gas by an adjustmentof the burner outlet flue cross-sections on the waste gas side and aconsequent distribution of the waste gas quantities over theregenerative heating chambers, the ratio of the burner outletcross-sections on the fresh gas side being automatically adjusted sothat with a positive supply of gas and air quantities the energies ofmovement of gas and air streams for each thermal value of the gas havesuch relative values that the intersection of the two streams takesplace on the bath surface, the burner outlet flue axes beingsimultaneously and correspondingly adjusted, the whole combustionprocess thus taking place on the bath surface only, the inclination ordirection of the burner outlet flue axes being changed in a continuousalternation, so that a to and fro travel of the point of impact of theflame produced by the interesecting gas and air streams over the wholebath surface is obtained and said change of the direction or inclinationof the burner outlet flue axes being limited to a certain range or pointof the bath surface.

5. The method of working industrial gas furnaces having air and gasheating checker chambers, a bath receiving hearth and burners atopposite ends of the hearth, said method comprising preheating thestreams of gas and air for combustion to an equal or predetermineddifferent temperature for streams takes place on the bath surface, the

burner outlet flue axes being simultaneously and correspondinglyadjusted, the whole combustion processthus takingplace on the bathsurface only,the inclination or direction of the burner outlet flue axesbeing changed in a continuous alternation so that a to and fro travel ofthe point of impact of the flame produced by the intersecting gas andair streams over the whole bath surface is obtained, said change of thedirection or inclination of the burner outlet flue axes being limited toa certain range point of the bath surface, the streams of gas and airreceiving such energies of movement during the to and frotravel of thepoint of -I f impact of the flame on the bath surface, which arerequired. for a larger or smaller distance of said point of'impact ofthe flame from the fresh gas burner, the burner,

outlet flue cross-sections being gradually narrowed or widened, andthe-ratio of the burner outlet cross-sections remaining constant duringsaid adjustments provided a change of the last-mentioned ratio is notnecessitated by a change of the calorific value of the gas. a I

6. A regenerative furnace having air and gas heating'checker chambers, abath receiving hearth, burners at opposite ends of the hearth and flapsin each burner outlet operable to regulate the cross-section thereof inaccordance with the thermic value of the,

gas. a

7. A regenerative furnace having air and gas heating checker chambers,abath receiving hearth, burners at opposite ends of the hearth, flaps ineach burner outlet operable to regulate the cross-section thereof inaccordance with the thermic value of the gas, a main spindle controllingthe positions of said flaps to effect the adjustment of thecross-section of said outlet and to effect further the shifting of theburner flue outlet axes owing to the necessary changes of thecross-sections during the to and fro travel of the flame and anauxiliary controllingv spindle adapted to act upon said flaps to adaptthe ratio of the burner outlet cross-sections to the instant calorificvalue of the gas.

8. A regenerative furnace having air and gas heating checker chambers, abath receiving hearthhuiners at opposite ends of the hea'rth,. flaps ineach burner outlet operable to negulete the cross 's'ection, thereof inaccordance with thethermie Value of the/gas, a main. spindledcdrltgollingl the positions of said flaps to effect the. "adjustment ofthe cross-sectioh of saidoutlet mid to effect fur flier thes'l liftingof the burner fluieofitlet 'txes owing to the necessary changes of theci'oss-sctions cluring the to and fro travel of the flame, an auxiliaryControlling spindle adapted to act upon said flaps to adapt the ratio ofthe bur'ner outlet cross-sections to the: instant vcalorific Value ofthe'gas and a gearing for e'ontrolling said spindles Wherebyth-e variousadjustments and a. reversing of said burners from their fresh gasp'ositin'n'to, the wzistegas position areauto- Inatieal1yeffected.- t iIg-tes'timfony whereof I have 'hereunto set WALT-HER SCHUCANY.-

